This invention relates to known suction cleaning devices connectable to a suction source for use in a swimming pool. One such device is sold under the name "Pool Vac", a registered trademark of Arneson Products Corporation of Corte Madera, Calif. The improvements to such a device are the subject of this application.
The above cited suction cleaning device is fluid powered by a suction source. There are two fluid flow paths within the housing. The primary flow path contains the primary turbine which drives the device. The secondary flow path contains the secondary turbine which steers the device. The primary and secondary flow paths join at the inlet of the primary turbine such that water from the primary fluid inlet joins the water from the secondary fluid outlet just before entry into the primary turbine.
In the prior art suction cleaning device, access to the primary turbine is often required if hard debris, such as acorns, get sucked up into the underside of the device and jam the turbine. To clean the hard debris, the entire bottom housing assembly with four screws must be removed in order to gain access to the primary turbine. These screws are often removed pool side, that is, at the point of use of the suction cleaning device. The screws were apt to fall into the pool or otherwise be lost. Moreover, it was difficult to replace the bottom housing assembly since various components, such as the rocker arms, had to be aligned with other mating components.
In this prior art, the bottom housing assembly was designed with a few grooved paths for optimum operation in a concrete pool. This bottom housing assembly also had two downwardly projecting feet to keep the suction cleaning device from hanging up on the main drain or light fixtures located in the swimming pool.
Because of the possibility of tears and scratches, these feet are not desirable for vinyl pools and must be covered. Therefore, an additional screw mounted external plate, which covered the feet and had different channeling configurations, was added for vinyl pool operation. In addition, the plate placed the channeling configurations closer to the pool surface which increases suction and is desirable for vinyl pools, which are typically provided with smaller pumps for their suction source.
A third accessory, a venturi or restrictor throat, could be added for vinyl pools to maximize suction where small filter pumps were used. This extra piece was accommodated by inserting it into the housing bottom and sandwiching it in position by attachment of the external cover piece.
Prior art models also had a strainer in order to block debris from entering the output port of the steering mechanism. In operation, one component of the secondary fluid flow would come in through a separate opening and then out through this output port, past the primary turbine and into the main vacuum hose. At times when the suction source would be shut off, back pressure could force debris into this exit port which could jam the gear box and lower secondary turbine. The strainer limits the likelihood of occurrence of such jams.